The MP0 ion optics transmits ions from the MP00 ion optics to the quadrupole mass analyzer. The MP0 ion optics includes an MP0 multipole, a neutrals blocker, and the TK1 and TK2 (Turner-Kruger) lenses.
The MP0 multipole is an array of square-metal rods that transmit ions. The curved design of the rods reduces noise by preventing neutral species and high-velocity clusters from entering the quadrupole mass analyzer. The MS applies an RF voltage to the rods to generate an electric field that guides the ions along the axis of the multipole. The MP0 includes DC drag potentials that push ions through this last high-pressure region and provide increased operational robustness. The MP0 DC offset voltage increases the translational kinetic energy of the ions as they leave MP00. The RF voltage causes charged ions to follow the curve of the rods, while neutral species do not follow the curve; instead, they strike the neutrals blocker and are removed from the beam.
NOTE
The MP0 multipole is designed so that the PCB halves can be separated for service maintenance cleaning.
| No. | Description | No. | Description |
|---|---|---|---|
1 | MP0 multipole | 3 | TK lens holder |
2 | Neutrals blocker |
The TK1 and TK2 lenses are metal disks with a circular hole in the center through which the ion beams passes. They act as a two-element cone lens. The MS applies an electrical potential to the lens to both accelerate (or decelerate) ions as they approach each lens and to focus the ion beam as it passes through each lens. The TK1 and TK2 lenses act as a vacuum baffle between the MP0 multipole and the quadrupole mass analyzer. They also shield MP0 from the RF voltage that the MS applies to the quadrupole mass analyzer, and vice versa.